1. Field of the Invention
The present invention relates to nasopharyngeal airways and more particularly to nasopharyngeal airways that allow drainage of fluids generated by the ostia of the various sinuses located in the skull and face.
2. Description of the Related Art
In the skull and face, various sinus ostia are located that generate fluids draining into the nasal cavity. These various sinuses include the frontal, maxillary, ethmoid, and sphenoid sinuses. As approximately a pint of sinus fluids are generated a day, the drainage of these fluids is an important aspect of good health. Should such fluids pool, collect, or otherwise be left undrained, sinus infections may occur. If the sinus ostia are not allowed drainage of their secretions, pressure may also build up causing headaches and other complications.
A nasopharyngeal airway (NPA) is generally a tubular device passing from the tip of one of the nares, or nostrils, to the oropharynx of the patient. Sterilized plastics and the like are considered common materials sufficiently flexible to accommodate the curved path the NPA must take in order to travel from the naris to the oropharynx. Generally, such NPAs are tubes with solid walls that do not allow any migration of sinus fluids (such as those generated by the sinus ostia) from the exterior of the NPA to its interior. While such NPAs have their uses, such uses are generally temporary in nature as longer term collection or blockage of the sinus fluids leads to the complications set forth above.
Below are several detailed descriptions of prior attempts in the art to achieve nasopharyngeal airways.
M. V. Downing, U.S. Pat. No. 4,821,715
This reference is directed to a nasopharyngeal airway. Referring to the figures, the patient 10 is provided with the nasopharyngeal airway 11 comprising a tube 12 which, when inserted through the nares 13, extends through the nasal passage 14 to the oropharynx 15 of the patient 10. The tube 12 has an inside wall 17 which defines an airway passage 18 (shown in FIG. 3). Several lumens 19 are formed within the inside wall 17 of the tube 12. The lumens 19 are operatively connected to an oxygen source 22. The airway described in the Downing patent includes no fenestrations.
R. F. Eisele, U.S. Pat. No. 4,852,565
This reference is directed to a fenestrated tracheostomy tube that provides a generally interference-free path through which a disposable inner cannula may be inserted. Referring to FIGS. 5 and 6, the improved fenestrated tracheostomy tube 40 has an outer cannula 42 that incorporates the fenestrations 44. The fenestrations 44 are positioned near the center of the arcuate length of the outer cannula, so as to be generally positioned in the center of the trachea of the patient, and can be described as two pairs of slotted fenestrations arranged in a chevron pattern. Both the tracheal insertion and chevron pattern depart from characteristics used in nasopharyngeal airways. In fact, the fenestrations in this device are used to allow the patient to breathe normally, allowing the patient to be weaned from the tracheostomy tube.
E. L. Heyden, U.S. Pat. No. 4,637,389
This reference relates to endotracheal and tracheostomy tubes and is directed to a tubular intubation device with an expansible channel for fluid collection. Referring to FIGS. 1, 5, and 9, a central fluid passage 24 provides respiratory gas exchange for the patient's lungs. An elongated channel 40 is integrally formed into the wall of passage 24 by way of innermost second wall portion 48 and is positioned to provide favorable access for secretions in a recumbent patient. Ports 42 present at spaced locations along the length of the passage 40 in the outer wall portion 46 allow fluid flow into the passage 40. Accumulated fluids may be removed by suction catheter 60. Active suctioning, not passive drainage, is required to remove the collected fluids. If the fluids are left uncollected, drainage may halt. No passive relief for pressure generated via the sinus ostia is disclosed.
J. T. Hanlon, U.S. Pat. No. 2,335,936
This reference is directed to a nasal dilating device for use only in the nares. The nasal dilating device 10 is made of an inert metal or plastic or other material not irritable to the mucous membrane. The device 10 having been inserted into the nasal passage of the patient permits air to be drawn inwardly through the openings 18 and the end opening 14 and into the lungs of the patient. The device does not extend to the oropharynx, does not allow intubation, and does not protect the delicate mucous membrane tissue of the sinuses. The inwardly deflecting wall sections 16 are alternated with strip-openings 17 to assist in the inward passage of air and also to permit untrammeled hair growth within the nasal passages. Thus, the end section 11 comprises alternating strip sections 16 and slotted opening sections 17 for air passage and not fluid drainage. The overall rigidity and configuration (overall shape) 18 prevents this device from operating as a nasopharyngeal airway and it is not meant for continuous use.
DeLuccia, deceased et al., U.S. Pat. No. 4,502,482
This reference is directed to an endotracheal tube complex (which is unlike a nasopharyngeal airway). Referring to FIGS. 1, 2 and 4, the end portion 22 is formed with a plurality of longitudinal slits 36 formed parallel to each other.
C. Kruger, U.S. Pat. No. 4,612,927
This reference is directed to an instrument for keeping clear the upper respiratory passages. Referring to the figures, note the plurality of slots 27 and 10 that are placed in parallel fashion along the laterally directed width of the device 1.
R. Gandi et al., U.S. Pat. No. 4,300,550
This reference is directed to a suction and oxygenation catheter. Referring to FIG. 1, the plastic tube 24 is inserted through the nasal passage 62 of the patient, and the tube 24 has at its furthermost end a plurality of openings 48, 50 for the passage of air therethrough. The distal positioning of these openings would not provide any advantages in an NPA.
K. Miner et al., U.S. Pat. No. 3,872,515
This reference is directed to rubber gloves. The surgical gloves are formed of a nonallergenic material such as silicone rubber.
A. Le Mitouard, U.S. Pat. No. 5,429,683
This reference is directed to a face mask for breathing. Referring to FIG. 2, the inside surface of the shell 1 of the mask receives a lining 6. The lining 6 is made of a flexible material such as a polyurethane foam covered in latex. However, if there are allergy problems, the skin of the lining may be provided with a silicone coating. Column 2, Lines 40-56.
In patients requiring long-term care, airway-management devices such as NPAs are sometimes required for the maintenance of a patent unobstructed airway. The same is sometimes similarly true for patients requiring emergency, acute, and/or chronic care. Without the ability of a nasopharyngeal airway to allow the release of pressure generated by the fluids secreted by the sinus and otic ostia, life-threatening infections can occur due to fluid accumulation. The eustachian tubes are particularly susceptible to such pressure and may suffer adversely should an infection establish itself. The increased pressure from such fluids cannot be relieved by nasal NPAs previously known in the art.
It would be to great advantage to provide a nasopharyngeal airway that provided means by which fluid pressure and accumulation could be respectively relieved and drained. Such an NPA may also function as a portal for introducing diagnostic probes and instruments for long term measurements of the patient.